Most NTSC System-M countries have an informal ban on channel 37 as well.

Since July 2000, channel 37 may also be used in the U.S. for medical telemetry equipment on a co-primary basis. This equipment must emit no more than one watt of effective radiated power, and is for use in hospitals and other such facilities.

Even this seemingly low power level can be troublesome for radio astronomy, which depends on detecting extraordinarily low signal strengths. Any use of the same frequencies raises the noise floor, thereby decreasing the signal-to-noise ratio, and making the work more difficult.

The channels displayed by cable converter boxes under these numbers are not on the same frequencies as their over-the-air counterparts; there are also virtual channel numbering schemes in use in digital television which do not map directly to fixed frequency channel assignments. As such, a "cable 37" channel may (and most often does) exist, but on a much lower frequency.

in the UK (many transmitters used by the Five network actually broadcast on channel 37)

in Western Europe, Channel 37 is used fairly widely as a relay transmitter frequency.

In Malaysia, NTV7 broadcasts in PAL on CCIR Channel 37 (599.25 MHz)

Channel 37 is not the same frequency as it is in the countries using the System-M/N standard. At least in the UK, 606–614 MHz is reserved for radio astronomy.

The UK's namesake "Channel 37", while different in frequency, was formerly part of a small group of channels reserved for non-broadcast purposes such as RF modulators in video players.[3] The UK-named 34-37 channel range is no longer reserved in this manner.

DVB-T adoption note : The tables above are not accurate for nations that have adopted DVB-T. The frequencies for audio and video are merged with DVB terrestrial television. The new DVB frequencies are rounded off to an even number in MHz as a general rule.

National Arrangements for Radio Astronomy different from ITU-R Radio Regulations

Armenia: no allocation

Austria: no allocation - only mention of No. 5.149

Bulgaria: no allocation

Belgium: assignment to radio astronomy (shared with active services)

Finland: no allocation

Estonia: no allocation

Iceland: no allocation

Liechtenstein: no allocation

Luxembourg: no allocation

Netherlands: primary status

Portugal: no allocation

Russian Federation: no allocation

Spain: no allocation

Sweden: no allocation

Turkey: no allocation

United Kingdom: no reference to No. 5.149

Legal note

No Allocation and Primary Status could be considered equivalent legal status. Very often the lack of allocation implies an internal regulatory coherence with ITU-R regulations freeing up this band for Astronomy.

Assignment and Primary Status could be considered equivalent legal statuses as well.